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Journal of mountain Science 2024年第8期21卷 2844-2854页

作者： CHEN Wenhua XIAng tian School of Civil Engineering Beijing Jiaotong UniversityBeijing 202303China

Water freezing in rock fractures causes volumetric expansion and fracture development through frost *** study introduces a novel analytical model to investigate how uneven freezing force and surrounding rock pressure influence fracture initiation,based on mass conservation,elasticity,and water-ice phase transition principles.A model for rock fracture initiation considering freezing temperature,uneven freezing expansion,in-situ stress,and lateral pressure was proposed based on fracture *** for stress intensity factors were developed and validated using the phase field *** effects of rock elastic modulus anisotropy and critical fracture energy density on fracture initiation were also *** results show that the values of KI and KII exhibit an upward trend as the freezing temperature,uneven expansion,in-situ stress,and lateral pressure *** uneven freezing expansion has the most significant influence on KI and KII values am.ng these *** the uneven freezing expansion coefficient increases to 0.5,the fracture initiation mode shifts from tensile fracture to shear *** the lateral pressure coefficient increases to 1,the fracture initiation mode shifts from tensile fracture to shear *** elastic modulus anisotropy causes fractures to propagate in a clockwise direction,form.ng a'butterfly'*** fracture energy density an isotropy causes counterclockwise deviation in propagation direction,resulting in branching paths and an'H'-shaped pattern.

关键词： Rock fractures Fracture water Uneven freezing expansion Phase field method Initiation angle Anisotropy

基于数值稳定型神经网络的Villain-Lai-Das Sarma方程的动力学标度行为研究

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物理学报 2024年第16期73卷 28-35页

作者：宋天舒夏辉中国矿业大学信息与控制工程学院徐州221116 中国矿业大学材料与物理学院徐州221116

Villain-Lai-Das Sarma(VLDS)方程因其能够有效描述分子束外延生长过程而在表面生长动力学等领域中备受关注.然而,长程关联噪声驱动下的VLDS方程的标度结果尚不明确,不同解析近似方法所得的标度结果仍不自洽.在数值模拟方面,由于非线性... 详细信息

Villain-Lai-Das Sarma(VLDS)方程因其能够有效描述分子束外延生长过程而在表面生长动力学等领域中备受关注.然而,长程关联噪声驱动下的VLDS方程的标度结果尚不明确,不同解析近似方法所得的标度结果仍不自洽.在数值模拟方面,由于非线性项的存在,VLDS方程一直存在数值发散的问题.当前主要引入指数衰减技术替换非线性项以缓解数值发散的问题,但是最近研究表明,这种方法会导致所获得的标度指数发生歧变.因此本文基于深度神经网络来表征VLDS方程中的各个确定项,并基于数值稳定型神经网络分别对含长程时间和空间关联噪声的VLDS系统进行有效的数值模拟.结果表明,我们所构建的深度神经网络具有良好的数值计算稳定性和泛化性,可以获得不同关联噪声驱动下的VLDS方程的可靠标度指数.同时,本文还发现长程时间关联噪声驱动的VLDS系统在时间关联指数较大时呈现谷堆状的表面形貌,而空间关联噪声驱动下的表面形貌则仍然呈现自仿射分形结构.

关键词：神经网络分子束外延生长 Villain-Lai-Das Sarma方程动力学标度

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Intracoronary thrombolysis combined with drug balloon angioplasty in a young ST-segment elevation myocardial infarction patient:A case report

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World Journal of Cardiology 2024年第9期16卷 531-541页

作者： Li-Qiong She De-Kui Gao Le Hong Yin tian hui-Zhen Wang Sheng Huang Department of Critical Care medicine Jiangyou Second People's HospitalJiangyou 621701Sichuan ProvinceChina Department of Cardiology Jiangyou Second People's HospitalJiangyou 621701Sichuan ProvinceChina Department of Interventional medicine Jiangyou Second People's HospitalJiangyou 621701Sichuan ProvinceChina

BACKGROUND The combination of acute ST-segment elevation myocardial infarction(STEmI)and gastric ulcers poses a challenge to primary percutaneous coronary intervention(PPCI),particularly for young *** role of drug-coated balloons(DCBs)in the treatment of de novo coronary artery lesions in large vessels remains unclear,especially for patients with *** strategy is to implement drug balloon angioplasty following the intracoronary administration of low-dose prourokinase and adequate *** SUmmARY A 54-year-old male patient presented to the emergency department due to chest pain on June 24,*** the first 3 minutes of the initial assessment in the emergency room,the electrocardiogram(ECG)showed significant *** was atrial fibrillation with ST-segment ***,atrial fibrillation terminated spontaneously and reverted to sinus *** after,the patient experienced *** ECG revealed torsades de pointes ventricular tachycardia.A few seconds later,it returned to sinus ***-sensitivity tropon in I was *** diagnosis was acute *** coronary angiography revealed subtotal occlusion with thrombus formation in the proximal segment of the left anterior descending *** the patient's age and history of peptic ulcer disease,after the intracoronary injection of prourokinase,percutaneous transluminal coronary angioplasty and cutting balloon angioplasty were conducted for thorough preconditioning,and paclitaxel drug-eluting balloon angioplasty was performed without any stents,achieving favorable *** A PPCI without stents may be a viable treatment strategy for select patients with STEmI,and further research is warranted.

关键词： STsegment elevation myocardial infarction Recombinant human prourokinase De novo coronary lesion Large vessels Drug-eluting balloon angioplasty Case report

Prediction of ball-on-plate friction and wear by ANN with data-driven optimization

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Friction 2024年第6期12卷 1235-1249页

作者： Alexander KOVALEV Yu tian Yonggang m.ng State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

For training artificial neural network(ANN),big data either generated by machine or measured from experiments are used as input to"learn"the unspecified functions defining the *** experimental data are fed directly into the optimizer allowing training to be performed according to a predefined loss *** predict sliding friction and wear at mixed lubrication conditions,in this study a specific ANN structure was so designed that deep learning algorithms and data-driven optimization models can be *** ball-on-plate friction and wear data were analyzed using the specific training procedure to optimize the weights and biases incorporated into the neural layers of the ANN,and only two independent experimental data sets were used during the ANN optimization *** the training procedure,the ANN is capable to predict the contact and hydrodynamic pressure by adapting the output data according to the tribological condition implemented in the optimization algorithm.

关键词： machine learning deep learning artificial neural network mixed lubrication

Numerical investigation on characteristics of interfacial wave of liquid film in gas-liquid two-phase flow using OpenFOAm

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Chinese Journal of Aeronautics 2024年第2期37卷 233-248页

作者： Xiaoqi mA Yueshe WAng Jiam.ng tian State Key Laboratory of multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China

Liquid film cooling as an advanced cooling technology is widely used in space *** operation of liquid film along the rocket combustion inner wall is crucial for thermal protection of rocket *** stability of liquid film is mainly determined by the characteristics of interfacial wave,which is rarely investigated right *** to improve the stability of thin film has become a hot *** view of this,an advanced model based on the conventional Volume of Fluid(VOF)model is adopted to investigate the characteristics of interfacial wave in gas-liquid flow by using OpenFOAm,and the mechanism of formation and development of wave is revealed intuitively through numerical *** effects from gas velocity,surface tension and dynamic viscosity of liquid(three factors)on the wave are studied *** can be found that the gas velocity is critical to the formation and development of wave,and four modes of droplets generation are illustrated in this ***,a gas vortex near the gas-liquid interface can induce formation of wave easily,so changing the gas vortex state can regulate formation and development of ***’s more,the change rules of three factors influencing on the interfacial wave are obtained,and the surface tension has a negative effect on the formation and development of wave only when the surface tension coefficient is above the critical value,whereas the dynamic viscosity has a positive effect in this ***,the maximum height and maximum slope angle of wave will level off as the gas velocity ***,the maximum slope angle of wave is usually no more than 38°,no matter what happens to the three factors.

关键词： Interfacial wave Gas-liquid Two-phase flow VOF model OpenFOAm

Deletion of a 1,049 bp sequence from the 5′UTR upstream of the SiHEC3 gene induces a seed non-shattering mutation in sesame

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Journal of Integrative Agriculture 2024年第8期23卷 2589-2604页

作者： m.ng Ju Guiting Li Qiuzhen tian Hengchun Cao Qin ma Yinghui Duan hui Guo Zhanyou Zhang Yingying Huang huili Wang Haiyang Zhang Hongmei miao The Shennong Laboratory Zhengzhou 450002China Henan Sesame Research Center Henan Academy of Agricultural SciencesZhengzhou 450002China Key Laboratory of Specific Oilseed Crops Genomics of Henan Province Henan Sesame Research CenterHenan Academy of Agricultural SciencesZhengzhou 450002China

Sesame is a labor intensive crop with limited mechanized harvesting mainly due to the seed shattering(SS)*** this study,we performed a genetic analysis of the seed-shattering resistance(SR)trait with a SR sesame mutant *** the SS type,the parenchyma cells in the abscission zone of the 12m07 mutant are arranged loosely but adhere to the seed *** analysis of six generations derived from 12m07(SR)×Xiangcheng Dazibai(SS)showed that the SR trait is recessive and controlled by a single gene *** mapping of the F2population with 888,619 variants(single-nucleotide polymorphisms(SNPs)and insertion-deletion(InDels))and 31,884 structural variations(SVs)determined that only SV12002 in the 5′upstream region of gene Sindi0765000(named SiHEC3)in Chr.3 was significantly associated with the SR ***3 encodes the bHLH transcription factor.A 1,049 bp deletion occurred in the 5′UTR of Sihec3 in ***3 is mainly expressed in developing placental tissues,with the expression peaking in capsules at 45 days after pollination.A dual-luciferase reporter assay in tobacco confirmed that the promoter activity of Sihec3 was reduced because of the deletion of the 1,049 bp promoter ***–protein interaction network analysis showed that HEC3 is co-expressed with nine key proteins,such as SHATTERPROOF1(SHP1)and SEEDSTICK(STK)which participate in the secondary wall biosynthesis of the abscission layer in *** findings of this study show the important function of Sihec3corresponding with the SR trait and supply the genetic information for breeding new varieties that are amenable to mechanized harvesting in sesame and other crops.

关键词： sesame(Sesamum indicum L.) association mapping seed shattering structure variation bHLH transcription factor

Interface property of dissimilar Ti-6Al-4V/AA1050 composite laminate made by non-equal channel lateral co-extrusion and heat treatment

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Defence Technology（防务技术） 2024年第3期33卷 197-208页

作者： Juan Liao m.ngm.ng tian Xin Xue School of mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion *** microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process *** electron microscopes(SEm),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion *** shear test was used to determine the mechanical properties of the interfacial diffusion *** experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral *** heat treatment processes affect the thickness of the diffusion *** the temperature and time of heat treatment increase,the thickness of the reaction layers increases ***,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer *** is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface *** characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.

关键词： Shear strength Co-extrusion Heat treatment microstructure Intermetallic compounds

A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory

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Defence Technology（防务技术） 2024年第2期32卷 232-241页

作者： Yunfei miao Guoping Wang Wei tian College of mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjingJiangsuChina Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingJiangsuChina

How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the mLRS considering the credibility of simulation system based on Bayesian theory is proposed in this *** of all,a comprehensive index system for the credibility of the simulation system of the firing precision of the mLRS is constructed combined with the group analytic hierarchy process.A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight *** Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution,and the rationality of prior information used in estimation model is discussed *** the simulation tests,the different evaluation methods are compared to validate the effectiveness of the proposed ***,the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%.

关键词： multiple launch rocket system Bayesian theory Simulation credibility mixed prior distribution Firing precision

Peritoneal fluid indocyanine green test for diagnosis of gut leakage in anastomotic leakage rats and colorectal surgery patients

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1825-1834页

作者： Yu Huang tian-Yang Li Jie-Feng Weng hui Liu Yu-Jie Xu Shuai Zhang Wei-Li Gu Department of Surgery Guangzhou First People's HospitalGuangzhou 510180Guangdong ProvinceChina

BACKGROUND Application of indocyanine green(ICG)fluorescence has led to new developments in gastrointestinal ***,little is known about the use of ICG for the diagnosis of postoperative gut leakage(GL).In addition,there is a lack of rapid and intuitive methods to definitively diagnose postoperative *** To investigate the effect of ICG in the diagnosis of anastomotic leakage in a surgical rat GL model and evaluate its diagnostic value in colorectal surgery *** Sixteen rats were divided into two groups:GL group(n=8)and sham group(n=8).Approximately 0.5 mL of ICG(2.5 mg/mL)was intravenously injected *** peritoneal fluid was collected for the fluorescence test at 24 and 48 *** patients with rectal cancer who had undergone laparoscopic rectal cancer resection plus enterostomies were injected with 10 mL of ICG(2.5 mg/mL)on postoperative day *** ostomy fluids were collected 24 h after ICG injection to identify the possibility of the ICG excreting from the peripheral veins to the enterostomy *** who had undergone colectomy or rectal cancer resection were enrolled in the diagnostic *** peritoneal fluids from drainage were collected 24 h after ICG *** ICG fluorescence test was conducted using Optomedic endoscopy along with a near-infrared fluorescent imaging *** The peritoneal fluids from the GL group showed ICG-dependent green fluorescence in contrast to the sham *** samples of ostomy fluids showed green fluorescence,indicating the possibility of ICG excreting from the peripheral veins to the enterostomy stoma in *** peritoneal fluid ICG test exhibited a sensitivity of 100%and a specificity of 83.3%for the diagnosis of *** positive predictive value was 71.4%,while the negative predictive value was 100%.The likelihood ratios were 6.0 for a positive test result and 0 for a negative *** The postoperative ICG test in a drainage tube is a valuable and simple t

关键词： Gut leakage Indocyanine green Anastomotic leakage model Diagnostic test Diagnostic technique

Women’s empowerment and food consumption:Evidence from female-headed households in Tanzania

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Journal of Integrative Agriculture 2024年第2期23卷 457-467页

作者： mosses Lufuke Xu tian College of Economics and management Nanjing Agricultural UniversityNanjing 210095China Department of Economics The University of DodomaDodoma 41218Tanzania College of Economics and management China Agricultural UniversityBeijing 100083China Academy of Global Food Economics and Policy China Agricultural UniversityBeijing 100083China

Despite the growing recognition of women’s increasing role in the household and corresponding empowerment programs in sub-Saharan Africa,intensive research on the relationship between women’s influence and household food consumption is *** the most recent(2017-2018)national household survey data from Tanzania,this study examined the influence of women’s empowerment on household food ***,we compared the monthly consumption of eight food categories between female-headed households(FHHs)and male-headed households(mHHs)using both descriptive statistics and the propensity score matching(PSm)***,we adopted the two-stage Linear Expenditure System and Almost Ideal Demand System model(LES-AIDS)to estimate income and price elasticities for the two household *** results show that FHHs consume bread and cereals,fish,oils and fats,vegetables,and confectionery(sugar,jam,honey,chocolate,etc.)more than ***,FHHs have a significantly higher income elasticity of demand for all food groups than *** are also more price elastic than mHHs in meat,fish,oils,fats,sugar,jam,honey,chocolate,etc.

关键词： women’s empowerment food consumption income elasticity price elasticity